Figure 7.

Methylation status of the six genes in 54 samples analyzed by pyrosequencing. (A) Each gene was methylated to a different extent in each sample. C, 34 cancer samples. N, 20 normal samples. Circle, methylation ratio of each sample. Filled circles indicate that the gene is methylated with the methylation ratio >25%. Bars, the mean and standard error of methylation ratios. P-values were calculated by t-test to compare distribution of methylation ratios between cancer (C) and normal (N) samples. Five genes (HIST1H3J, SHOX2, PHKG2, TLX3, and HOXA7) showed significantly higher methylation in cancer (P < 0.05, t-test). POU4F2 tended to show higher methylation in cancer (P = 0.07, t-test). (B) Heatmap for methylation status of the 54 analyzed samples. Among the 34 papillary thyroid cancer samples, 26 were aberrant methylation(+) in at least one of six genes, while eight had no methylation. In Table 4, the number of cancer samples with aberrant methylation (n = 26) and the number of samples without aberrant methylation (n = 8) refer to these data.